Optical fiber amplifiers that receive coherent light of relatively low power from a seed laser and amplify that light with fiber laser amplifiers are known. When the systems are to be used for such applications as target marking, target ranging, imaging, and tracking, and LIDAR, among others, a primary objective has been to obtain a high-power, single mode output, or output with relatively low multimode content. This is particular difficult because of the necessity of controlling amplified spontaneous emission (ASE), controlling the excitation of unwanted modes, and reducing the effects of non-linearity. One technique that has been proposed includes that of cascaded, pulse-pumped amplifiers where pumping is synchronized with the pulse to be amplified. Such a system is shown in U.S. Pat. No. 5,933,271. This is however limited to relatively low pulse peak powers when compared to conventional solid state lasers that are capable of peak powers in the hundreds of kilowatts to megawatts.